Area Forecast Discussion
Issued by NWS Paducah, KY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
000
FXUS63 KPAH 261747
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
1247 PM CDT TUE APR 26 2016

.UPDATE...
Issued at 1246 PM CDT Tue Apr 26 2016

Updated aviation discussion for the 18z TAF issuance

&&

.SHORT TERM...(Today through Thursday night)
Issued at 227 AM CDT Tue Apr 26 2016

Warm sector/boundary induced convection will begin early this
period, and continue (pcpn chances) more or less off and on
through much of the short term forecast period.

Day 1 risk is marginal today/tonight, with best instability/lift
staying to our west. Slgt risk advances eastward for Day 2, with
warm front induced convection early Wed, followed by best chance
strong to svr storms Wed pm/evening as warm front lifts north, and
cold front takes shape/approaches from the west. It appears best
instability/lift will be just to our south, but Slgt risk does
extend as far north as STL area. Upped PoPs to categorical during
this best chance time period.

Front/system makes passage Wed night, and only lingering pops
remain thereafter. Temps generally around or in the 80s for highs
and around or in the 60s for lows will rule through the duration
of the short term forecast.

.LONG TERM...(Friday through Monday)
Issued at 227 AM CDT Tue Apr 26 2016

The main feature of interest in the long term period will be another
storm system very similar to the mid-week system. The track of the
500 mb shortwave will be nearly identical to the Wednesday system.
The surface low track is not as clear-cut, but most guidance takes
it along a similar path to our north.

As far as the day-to-day specifics, for Friday there is still some
model variability as to how quickly low-level moisture will return.
A 500 mb ridge axis will be over our region most of the day.
However, the 850 mb flow will become southerly later in the day
across much of Missouri. Some showers are possible where the moist
850 mb flow overrides easterly surface winds, which will be mainly
over southeast Missouri in the afternoon. Surface and elevated
instability parameters indicate thunder is unlikely Friday.
Coverage of showers will increase Friday night as moist low-level
flow overspreads the entire region.

On Saturday, the 500 mb closed low will move northeast into
Nebraska. The associated surface low will likely advance northeast
across the Plains, dragging a warm front north across our region. As
stronger upper forcing overspreads the warm frontal boundary,
coverage of showers and elevated storms will become widespread. Pops
will be in the likely category. Instability will increase slightly,
but widespread clouds and precip will limit surface-based
instability.

The system will slow down significantly on Sunday. The 500 mb low
will be quasi-stationary over the Nebraska vicinity. The associated
surface low will occlude to our northwest, probably in northern
Missouri. The model consensus has trended slower with the progress
of the cold front or occluded front, which is now forecast to cross
our region late Sunday or Sunday evening. The highest convective
potential during this multi-day event will be late Sunday along the
front. However, the 00z gfs/ecmwf indicate the best moisture and
instability will have trouble extending as far north as the Lower
Ohio Valley. The event is still several days away, and the models
could trend even slower.

On Monday, westerly low-level flow behind the front will bring
somewhat cooler air. The 500 mb trough will lag across the Plains
early next week, keeping our region in a moist southwest flow aloft.
There should be considerable cloudiness along with scattered
showers.

&&

.AVIATION...
Issued at 1246 PM CDT Tue Apr 26 2016

MVFR conditions will prevail through much of the TAF period. VFR
conditions will continue for the next hour or two until a broad
area of showers and thunderstorms passes through the Quad State
area this afternoon and evening, causing sharp ceiling and
visibility changes and gusty winds. After convection and showers
move out this evening, MVFR cigs and south winds AOB 7 kts will
prevail until near sunrise. While some uncertainty exists
regarding tomorrow`s forecast, at this time it is likely that
another wave of convection will pass through in the morning hours.

&&

.PAH Watches/Warnings/Advisories...
IL...None.
MO...None.
IN...None.
KY...None.
&&

$$

AVIATION UPDATE...BP2



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.